1. Field of the Invention
This disclosure relates generally to system operating constraints within an ambient temperature range, and more specifically, to a system and method for enabling maximum performance operation within an extended ambient temperature range including extremely low ambient temperatures.
2. Description of the Related Art
Conventional manufacturing methods of semiconductor devices often dictated that different versions of a semiconductor device be designed and manufactured according to different operating specifications. For example, commercial grade parts were designed to meet commercial standards, whereas military grade parts were designed to meet more stringent military standards to enable operation during harsh conditions or in harsher environments. Commercial grade parts, for example, were specified to operate at a maximum performance level only down to a relatively modest temperature level, such as 0° C., whereas military grade parts were specified to operate at the maximum performance level within an extended ambient temperature range, such as down to −40° C.
Manufacturing multiple version of the same device to meet different specifications is inefficient and costly. Furthermore, many commercial customers have been requesting that commercial grade devices meet more rigid standards to enable operation under harsher operating conditions while operating within the same power envelope, such as an extended operating temperature range. For example, base stations of commercial wireless networks are often exposed to extreme weather conditions. Commercial airliners are continuously exposed to frigid temperatures at high altitudes. Whereas the power envelope is a function of the maximum frequency at the maximum temperature (e.g., 85° C.), the customer often has the expectation that the part operates at a maximum frequency and/or maximum performance level even when exposed to temperatures below the normal ambient temperature range. These conditions make it challenging to acquire sufficient yield of silicon that meets both ends of the operating corners.
External components, such as external heaters or heating pads or the like, were often provided to heat up electronic commercial devices to a predetermined minimum operating level so that the system could operate at maximum performance. Such external devices were costly, and in some cases, raised additional safety concerns. For example, a heater or heating pad used to heat up electronics on an airliner posed additional fire hazard risks.